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You need to get permission from the court to do so to get signed off on your hours. You would want to talk to the court clerk (unless there's a specific contact to deal with regarding community service, in which you would want to talk with that person). "Community service" is an alternative form of "punishment", and as such it's entirely up to the judge to determine what that means. In other words, community service does NOT mean what you think it means, but rather means what the judge thinks it means, and that means that you're going to have to get permission from the court for whatever community service you do. Often the court will give orders and other guidance documents as to what this means, but not necessarily.
As to getting the paper signed for your hours, that would be with the organization that handles the online community service. You'd have to contact them. They probably have a "contact number" or "contact information" link on their website, but regardless who you go through to do community service, it's going to be the organization that signs off on it, and ultimately that's a real person that's going to put pen to paper (or at least finger to keyboard to write a letter to the court) and so you're going to have to get the organization to sign off on it.
Hope that clears things up a bit. If you have any other questions, please let me know. If not, and you have not yet, please rate my answer AND press the "submit" button, if applicable.
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